JP6962809B2 - Vehicle propulsion shaft - Google Patents

Description

The present invention relates to a propulsion shaft for a vehicle.

A torsional damper is a device that attenuates rotational fluctuations that occur in a prime mover or transmission at a propulsion shaft. As a conventional example of a torsional damper, an inner ring having a bolt hole, a plurality of elastic bodies extending radially to the outside of the inner ring, and an annular mass body in which the elastic bodies are adhered to the inner circumference and held. Those equipped with. Since the mass body rotates at high speed, the torsional damper is required to be securely attached in the front-rear direction and the rotation direction of the vehicle.

As an example of mounting a torsional damper, as shown in Patent Document 1, a structure in which the inner ring is sandwiched between a companion flange of a transmission or a final reduction gear and a flange yoke of a propulsion shaft and fastened together with bolts is used. Can be mentioned. As a result, the torsional damper is fixed to the propulsion shaft in the vehicle front-rear direction and the rotation direction. Further, as another mounting example, as shown in Patent Document 2, there is a structure in which the inner ring is directly fitted to the propulsion shaft and mounted. Further, as shown in Patent Document 3, there is also a structure in which an elastic body is vulcanized and bonded to the outer periphery of a member constituting the propulsion shaft.

Japanese Unexamined Patent Publication No. 5-223140 Japanese Unexamined Patent Publication No. 2006-207751 Japanese Unexamined Patent Publication No. 2016-90056

The torsional damper has a large mass to some extent in order to generate a predetermined damping force. On the other hand, since the propulsion shaft is arranged in the floor tunnel on the lower surface of the vehicle body, it may be difficult to attach the torsional damper to the connecting portion between the propulsion shaft and the transmission or the final reduction gear due to space restrictions. ..

In this case, it is conceivable to attach the member in the vicinity of the intermediate bearing arranged in the center of the propulsion shaft, but depending on the structure around the intermediate bearing, there may be no member corresponding to the flange to be sandwiched. In such a case, as described in Patent Documents 2 and 3, a torsional damper is attached by fitting or adhering to a member constituting the propulsion shaft.

The techniques of Patent Documents 2 and 3 have a structure in which the positioning of the torsional damper in the vehicle front-rear direction and the rotation direction with respect to the propulsion shaft is exclusively based on press-fitting and adhesive. However, since the propulsion shaft is located at the bottom of the vehicle body, it is easily affected by muddy water and salt. If corrosion occurs around the mounting part of the torsional damper, rattling of the fitting part and deterioration of the adhesive may progress, and the positioning function of the torsional damper in the vehicle front-rear direction and the rotation direction may be impaired. ..

Further, when the intermediate bearing is attached to the shaft member connected to the constant velocity joint, if the torsional damper is arranged between the intermediate bearing and the constant velocity joint, the space for arranging the torsional damper is required. There is a problem that the length of the shaft member becomes long.

The present invention was created to solve such a problem, and is a vehicle capable of stably fixing a torsional damper without misalignment while suppressing an increase in the length of a shaft member pivotally supported by a bearing. The purpose is to provide a propulsion shaft for use.

In order to solve the above-mentioned problems, the present invention is a vehicle propulsion shaft provided with a shaft member pivotally supported by a bearing and one end connected to a constant velocity joint, and a torsional damper attached to the shaft member. The torsional damper is formed on the outer periphery of the stopper piece and the stopper piece which is fitted onto the shaft member between the bearing and the constant velocity joint and abuts on the bearing to position the bearing in the axial direction. It is characterized by including an elastic body and a mass body formed on the outer periphery of the elastic body.

According to the present invention, the torsional damper can be stably fixed to the propulsion shaft by using the stopper piece without press-fitting or using an adhesive. According to the present invention, the stopper piece also has a function of preventing the bearing from coming off and a function of attaching the torsional damper to the shaft member. As a result, in the structure in which the torsional damper is arranged between the bearing and the constant velocity joint, it is not necessary to separately secure the arrangement space for the bearing retaining member and the arrangement space for the torsional damper, and the shaft is correspondingly increased. It is possible to suppress the increase in the length of the member. In addition, the number of parts can be reduced and the assembly process can be simplified.

Further, in the present invention, an inner ring member connected to the vehicle body side is externally fitted to the outer ring of the bearing, and the stopper piece is arranged closer to the constant velocity joint than the inner ring member, and the elastic body and the elastic body. It is provided with a damper forming portion to which a mass body is attached and a bearing contact portion having an outer diameter smaller than that of the damper forming portion and which is arranged inside the inner ring member and abuts on the inner ring of the bearing. It is characterized by.

According to the present invention, muddy water and chipping that bounce toward bearings can be effectively protected by a torsional damper.

Further, in the present invention, the constant velocity joint includes an outer case and boots for sealing the inside between the outer case and the shaft member, and the boots are fixed to the stopper piece. It is a feature.

According to the present invention, it is not necessary to secure a space for the fitting portion of the boot on the outer circumference of the shaft member. As a result, it is possible to suppress an increase in the length of the shaft member.

Further, the present invention is characterized in that the stopper piece is formed with a communication passage for communicating the inside of the constant velocity joint and the bearing.

According to the present invention, the pressure in the constant velocity joint can be released to the bearing mounting space by the continuous passage. Since the communication passage communicates the inside of the constant velocity joint with the bearing, there is almost no risk of muddy water or the like entering from the outside.

Further, the present invention is characterized in that the stopper piece and the shaft member are integrally rotated by spline fitting.
Further, the present invention is characterized in that the stopper piece and the shaft member are integrally rotated by a sphere that is locked in both recesses.

According to the present invention, it is possible to prevent the stopper piece from rotating with respect to the shaft member with a simple structure.

According to the present invention, the torsional damper can be stably fixed to the propulsion shaft without any misalignment while suppressing the increase in the length of the shaft member.

It is a side sectional view of the propulsion shaft of the 1st Embodiment of this invention. It is an enlarged view of the main part of FIG. It is a side sectional view of the propulsion shaft of the 2nd Embodiment of this invention. It is an enlarged view of the main part of FIG. FIG. 3 is a sectional view taken along line VV in FIG.

Two embodiments of the present invention will be described. In the description of each embodiment, the same components are designated by the same reference numerals, and duplicate description will be omitted.

"First embodiment"
In FIG. 1, the vehicle propulsion shaft (hereinafter, simply referred to as a propulsion shaft) 20 is mounted on, for example, an FF (Front-engine Front-drive) -based four-wheel drive vehicle. The propulsion shaft 20 is arranged below the floor panel (not shown) so as to extend in the front-rear direction of the vehicle, and the power from the transmission (not shown) at the front of the vehicle body is transferred to the final deceleration device (not shown) at the rear of the vehicle body. Communicate to.

The propulsion shaft 20 is a stub which is a shaft member arranged between the first pipe material 21 near the front of the vehicle, the second pipe material 22 near the rear of the vehicle, and the first pipe material 21 and the second pipe material 22. A constant velocity joint 24 for connecting the shaft 23, the first pipe member 21, and the stub shaft 23 is provided. The rear end of the first pipe material 21 is joined to the front end of the outer case 25 of the constant velocity joint 24 by welding or the like. The front end of the second pipe member 22 is joined to the rear end of the stub shaft 23 by welding or the like. Grease is sealed inside the constant velocity joint 24.

The constant velocity joint 24 is, for example, a tripod type constant velocity joint. The constant velocity joint 24 is an inner member 27 having a bottomed cylindrical outer case 25 arranged with the opening facing backward and a roller 26 sliding in the axial O direction along the sliding groove of the outer case 25. And have. The front end of the stub shaft 23 is connected to the inner member 27 by spline fitting.

The inside of the outer case 25 is sealed with boots 28 provided to prevent the outflow of grease and the ingress of muddy water, dust, and the like. The boot 28 is a rubber member. One end of the boot 28 is attached to the outer case 25 via an adapter 29. The adapter 29 is a substantially cylindrical sheet metal member having openings at the front and rear ends, and the front end side is fitted and fixed around the rear end of the outer case 25. A folded portion 29A that is folded inward is formed at the rear end of the adapter 29. One end of the boot 28 is sandwiched and fixed to the folded-back portion 29A, once extended forward, then folded inward and extended rearward, and the other end is fastened to the outer peripheral surface of the stub shaft 23 by a band 30.

The constant velocity joint 24 is not limited to the tripod type, and may be a double offset type, a barfield type, or the like.

The stub shaft 23 has a stopper piece fitting portion 31 formed behind the fastening portion of the band 30 and fitted with the stopper piece 2 described later, and a bearing 41 formed behind the stopper piece fitting portion 31 and described later outside. The bearing fitting portion 32 to be fitted, the bearing regulation portion 33 formed behind the bearing fitting portion 32 to have a larger diameter than the bearing fitting portion 32, and the rear end formed to have a larger diameter behind the bearing regulation portion 33. Is provided with a pipe joint portion 34 for joining with the second pipe material 22.

The stub shaft 23 is supported by the vehicle body by the intermediate bearing body 40. The intermediate bearing body 40 includes a bearing 41 that is externally fitted to the bearing fitting portion 32 of the stub shaft 23, a cylindrical inner ring member 42 that is externally fitted to the bearing 41, and an annular shape that is arranged outside the diameter of the inner ring member 42. The anti-vibration member 43, the outer ring member 44 arranged outside the diameter of the anti-vibration member 43, the annular portion 48 outerly fitted to the outer ring member 44, and the bracket 49 joined to the annular portion 48. I have.

The inner ring member 42 is a metal member exhibiting an annular shape, and is externally fitted to the outer ring of the bearing 41. The anti-vibration member 43 is an annular rubber member that attenuates vibration from the stub shaft 23 and reduces transmission of vibration to the vehicle body. The inner ring member 42 is vulcanized and welded to the inner peripheral surface of the vibration isolator member 43. The inner ring of the bearing 41 is sandwiched between the stopper piece 2 and the bearing regulating portion 33, which will be described later, to prevent the bearing 41 from coming off in the O-axis direction. Seal members 46 and 47 are provided between the inner ring member 42 and the stopper piece 2 and between the inner ring member 42 and the bearing regulating portion 33 to prevent muddy water, dust, etc. from entering the bearing 41, respectively. ing. The outer ring member 44 is an annular metal member, and is fixed to the lower part of the vehicle body via an annular portion 48 and a bracket 49.

In the stub shaft 23, a convex portion 35 projects from the bearing restricting portion 33 and the pipe joint portion 34 in the outward diameter direction so as to close a gap between the bearing restricting portion 33 and the rear end of the inner ring member 42. Has been done. The convex portion 35 suppresses the intrusion of muddy water, dust, etc. into the seal member 47.

"Tortional damper"
As described above, the torsional damper 1A is attached to the stub shaft 23 pivotally supported by the intermediate bearing body 40. The torsional damper 1A is externally fitted into the stopper piece fitting portion 31 of the stub shaft 23 between the bearing 41 and the constant velocity joint 24, and is in contact with the bearing 41 to position the bearing 41 in the axial center O direction. 2, an elastic body 3 formed on the outer periphery of the stopper piece 2, and a mass body 4 formed on the outer periphery of the elastic body 3 are provided. The torsional damper 1A has a propulsion shaft 20 by adding an auxiliary mass body 4 via an elastic body 3 when vibration occurs in the rotation direction of the propulsion shaft 20 due to, for example, torque fluctuation of the prime mover. It is responsible for suppressing the resonance phenomenon around the natural frequency of.

In FIG. 2, the stopper piece 2 is, for example, a metal cylindrical member, and is preferably formed by cold forging. The stopper piece 2 has a large outer diameter damper forming portion 5 arranged closer to the constant velocity joint 24 with a slight gap C from the front end of the inner ring member 42, and an outer diameter smaller than that of the damper forming portion 5. It has a shape including a bearing contact portion 6 extending rearward from the rear end of the damper forming portion 5. The damper forming portion 5 has an outer diameter dimension that is substantially the same as the outer diameter dimension of the inner ring member 42. The elastic body 3 made of a rubber member is adhered to the outer peripheral surface of the damper forming portion 5 by vulcanization adhesion, and the annular mass body 4 is adhered to the outer peripheral surface of the elastic body 3 by vulcanization adhesion.

The bearing contact portion 6 is arranged inside the inner ring member 42, and its rear end is in contact with the front end surface of the inner ring of the bearing 41. The seal member 46 is provided between the inner circumference of the inner ring member 42 and the outer circumference of the bearing contact portion 6. On the outer periphery of the bearing contact portion 6 on the front side of the seal member 46, a convex portion 7 is provided so as to close the gap between the bearing contact portion 6 and the inner circumference of the inner ring member 42 in the outward diameter direction. By forming the gap together with the gap C by the convex portion 7, the intrusion of muddy water, dust, etc. into the seal member 46 is suppressed.

The front end of the stopper piece 2 is prevented from coming off by a snap ring 8 engaged with the outer circumference of the stub shaft 23. As the stopper piece 2 retaining member, a nut or the like may be used in addition to the snap ring 8.

As a means for integrally rotating the stopper piece 2 with the stub shaft 23, a structure in which the sphere 11 is locked in both recesses can be mentioned. A concave groove 9 extending in the axial O direction is formed on the inner circumference of the bearing contact portion 6 of the stopper piece 2. On the other hand, a locking hole 10 is formed on the outer periphery of the stopper piece fitting portion 31 of the stub shaft 23 so that a sphere 11 such as a steel ball protrudes from the outer periphery of the stopper piece fitting portion 31 in the locking hole 10. It is locked. The sphere 11 is located inside the concave groove 9. As described above, the stopper piece 2 rotates integrally with the stub shaft 23 by the sphere 11 that locks in both the concave groove 9 and the locking hole 10. Further, the stopper piece 2 and the stub shaft 23 may be integrally rotated by spline fitting.

According to the propulsion shaft 20 of the first embodiment, the torsional damper 1A can be arranged in a space-efficient manner in the vicinity of the bearing 41 in which a relatively large space is secured on the vehicle body floor where space is often restricted. Specifically, the stopper piece 2 also has a function of preventing the bearing 41 from coming off and a function of attaching the torsional damper 1A to the stub shaft 23 (inner ring function). As a result, in the structure in which the torsional damper 1A is arranged between the bearing 41 and the constant velocity joint 24, it is not necessary to separately secure the arrangement space of the retaining member of the bearing 41 and the arrangement space of the torsional damper 1A. Therefore, it is possible to suppress the increase in the length of the stub shaft 23. In addition, the number of parts can be reduced and the assembly process can be simplified.

A damper forming portion 5 which is arranged closer to the constant velocity joint 24 than the inner ring member 42 and to which the elastic body 3 and the mass body 4 are attached, and an outer diameter smaller than that of the damper forming portion 5, and is inside the inner ring member 42. By providing the stopper piece 2 provided with the bearing contact portion 6 which is arranged and abuts on the inner ring of the bearing 41, muddy water and chipping splashing toward the bearing 41 can be effectively protected by the torsional damper 1A. In particular, in the case of the present embodiment, since the torsional damper 1A is arranged in front of the bearing 41, muddy water that invades the inside of the inner ring member 42 from the front and splashes toward the bearing 41 while the vehicle is running. And chipping can be protected by the torsional damper 1A, and the durability of the bearing 41 is improved.

By integrally rotating the stopper piece 2 and the stub shaft 23 by a sphere 11 that locks in both the concave groove 9 and the locking hole 10, or by integrally rotating the stopper piece 2 and the stub shaft 23 by spline fitting. The stopper piece 2 can be prevented from rotating with a simple assembly operation. Since no press-fitting or adhesive is used for the stub shaft 23, it is not affected by muddy water or salt.

"Second embodiment"
In the torsional damper 1B according to the second embodiment shown in FIGS. 3 and 4, the boots 28 of the constant velocity joint 24 are externally fitted and fixed to the stopper piece 2 with respect to the torsional damper 1A of the first embodiment. The difference is that the stopper piece 2 is formed with communication passages 13 and 14 for communicating the inside of the constant velocity joint 24 and the bearing 41.

The stopper piece 2 is formed with a boot fitting portion 12 that extends forward from the front end of the damper forming portion 5 and externally fits into the stopper piece fitting portion 31 of the stub shaft 23. The boot 28 of the constant velocity joint 24 is fitted on the outer circumference of the boot fitting portion 12 and fastened by the band 30.

On the inner circumference of the stopper piece 2, a communication passage 13 is formed along the axis O from the front end to the rear end of the stopper piece 2. When the inner diameter of the front end of the boot fitting portion 12 of the stopper piece 2 is chamfered, the mouth portion of the snap ring 8 and the communication passage 13 communicate with each other through the chamfer. The radial distance between the axis O and the communication passage 13 is sufficiently smaller than the inner diameter of the outer case 25 of the constant velocity joint 24, and is about half of the inner diameter of the outer case 25. As shown in FIG. 5, for example, the communication passage 13 is formed as a groove having a rectangular cross section. Further, at the rear end of the stopper piece 2, that is, the rear end of the bearing contact portion 6, the space S (FIG. 4) surrounded by the front end of the bearing 41 and the seal member 46 and the communication passage 13 are communicated with each other. In addition, a communication passage 14 is formed along the radial direction of the axis O. The communication passage 14 is also formed as, for example, a groove having a rectangular cross section.

According to the propulsion shaft 20 of the second embodiment, it is not necessary to secure a space for the fastening portion of the boot 28 on the outer circumference of the stub shaft 23 by fitting the boot 28 of the constant velocity joint 24 to the stopper piece 2. .. As a result, it is possible to suppress an increase in the length of the stub shaft 23.

According to the propulsion shaft 20 of the second embodiment, the pressure in the constant velocity joint 24 can be released to the mounting space of the bearing 41 by the communication passages 13 and 14. Since the communication passages 13 and 14 communicate the inside of the constant velocity joint 24 with the mounting space of the bearing 41, there is almost no risk of muddy water or the like entering from the outside. Since the communication passage 13 is located sufficiently closer to the axis O than the inner circumference of the outer case 25, the grease accumulated on the inner circumference of the outer case 25 does not enter the communication passage 13.

The preferred embodiment of the present invention has been described above. In the two embodiments, the configuration in which the intermediate bearing body 40 is arranged behind the constant velocity joint 24 is specified, but the present invention can also be applied to the configuration in which the constant velocity joint 24 is arranged behind the intermediate bearing body 40. ..

1A, 1B Tortional damper 2 Stopper piece 3 Elastic body 4 Mass body 5 Damper forming part 6 Bearing contact part 7 Convex part 8 Snap ring 9 Concave groove 10 Locking hole 11 Sphere 12 Boot fitting part 13, 14 Communication groove 20 Vehicle propulsion shaft 21 1st pipe material 22 2nd pipe material 23 Stub shaft (shaft member)
24 Constant velocity joint 28 Boot 40 Intermediate bearing body 41 Bearing

Claims (4)

A vehicle propulsion shaft provided with a shaft member that is pivotally supported by a bearing and one end of which is connected to a constant velocity joint, and a torsional damper that is attached to the shaft member.
The torsional damper is
A stopper piece that is fitted onto the shaft member between the bearing and the constant velocity joint, abuts on the bearing, and positions the bearing in the axial direction.
An elastic body formed on the outer circumference of the stopper piece and
A mass body formed on the outer circumference of the elastic body and
Equipped with a,
The constant velocity joint comprises an outer case and boots that seal the inside between the outer case and the shaft member.
The boot is fixed to the stopper piece,
The stopper piece is formed with a communication passage that communicates the inside of the constant velocity joint with the bearing.
The communication passage includes a groove formed on the inner circumference of the stopper piece from the front end to the rear end of the stopper piece along the axial center of the shaft member.
Propulsion shaft for vehicles characterized by this. An inner ring member connected to the vehicle body side is externally fitted to the outer ring of the bearing.
The stopper piece is
A damper forming portion that is arranged closer to the constant velocity joint than the inner ring member and to which the elastic body and the mass body are attached.
A bearing contact portion having an outer diameter smaller than that of the damper forming portion, which is arranged inside the inner ring member and abuts on the inner ring of the bearing.
The propulsion shaft for a vehicle according to claim 1, wherein the propulsion shaft for a vehicle is provided. The vehicle propulsion shaft according to claim 1 or 2 , wherein the stopper piece and the shaft member are integrally rotated by spline fitting. The vehicle propulsion shaft according to claim 1 or 2 , wherein the stopper piece and the shaft member are integrally rotated by a sphere that is locked in both recesses.

Images